Gestion app isn't working, anyone else experiencing this?

Hi, I’ve tried installing and uninstalling a few times with no success but get the same errors each time , see error messages in browser and log, any help appreciated please!
In Browser - Internal Server Error
The server was unable to complete your request.
If this happens again, please send the technical details below to the server administrator.
More details can be found in the server log.
Technical details
Remote Address: ****
Request ID: YafApcPb300EMaW33EE3nwAAFil

In Log

Level App. Message. Time
error index ParseError: syntax error, unexpected. 2021-12-01T18:36:21+0000
‘String’ (T_STRING), expecting function
(_FUNCTION) or const (T_CONST)

I experience the same thing. What is php version you’re using? Mine is php 7.3, and I saw at project github page a solution, that updating php to 7.4 version can solve this issue.

I didn’t try this, because I need to make a fullbackup of my server configuration first.